DE19805289A1 - Position adjustment device for a steering column - Google Patents

Description

This invention relates to a position adjusting device for an adjuster bare automotive steering column.

A motor vehicle steering column usually includes a tubular one Column jacket, a steering shaft rotatably carried on the column jacket and a steering wheel on the steering shaft. If the column jacket up and swivels down to the vertical position of the steering wheel to adjust, the steering column is "adjustable in inclination" or "inclination bar ". If the length of the column jacket is changed the can to adjust the horizontal position of the steering wheel is the Steering column marked as "telescopically adjustable" or "telescopic" net. They are position adjustment devices for tiltable and / or telescopic pische steering columns known in which a pair of vertical sides of a sta tional carrier by a lever-operated screw or by a he actuated rotary cam is clamped to the column jacket to pass through Friction the position of the pillar shell relative to the vehicle body to hold on. The performance of such a position adjustment device under extreme circumstances, e.g. B. during an impact on the Steering wheel, to maximize, it is also known on the stationary carrier and to form racks on the steering column, which comb when the ver tical sides of the stationary support clamped to the column jacket are. With such position adjusting devices, however, the Racks in the event of a tip-to-tip engagement between teeth  one of the racks and teeth on the other of the racks do not comb smoothly.

This invention is a new and improved position adjuster for an adjustable motor vehicle steering column that has a first rack, a cam block that is in a linear motion on the first tooth rod to and from it can be moved, a rack shoe, on which a second rack is provided and on the cam block for a linear movement as a unit with it and for one Pivotal movement is mounted relative thereto, and comprises a spring which the rack shoe in a tilted position relative to the cam block pretensioned. One end tooth of the second rack stands with one mating tooth of the first rack engaged when the cam block is advanced to the first rack in a linear movement. The force reaction of the matching tooth on the end tooth swivels the Rack shoe around a center line relative to the cam block the cam block into a position parallel to the first rack in which comb the first and second racks. In the event that a Tip of the end tooth meets a tip of the matching tooth, displaces one Pivotal movement of the rack shoe around the center line on the Cam block the tip of the end tooth to a flank of the matching one Tooth, thereby aligning the tips of the teeth on the first Rack with the tips of the teeth on the second rack and a corresponding disruption of the smooth engagement between the first and to prevent the second racks. A preferred execution shape of the position adjusting device comprises a first pair of racks, to hold the vertical adjustment of the steering column, a second pair Racks to hold the horizontal adjustment of the steering column, and a lever-operated cam means that vertically and vertically the steering column  holds and loosens rizontally by simultaneously removing the first and second Engages and disengages pairs of racks.

The invention will be exemplified below with reference to the drawing wrote in this is

Fig. 1 is a fragmentary elevational view of a motor vehicle steering column with a position adjustment device according to this invention,

FIG. 2 is an enlarged sectional view taken generally along the plane shown by lines 2-2 in FIG. 1 .

Is a sectional view taken. 3 along the nien by Li 3-3 generally in FIG. 2 plane shown,

Fig. 4 is similar to Fig. 3 showing components of the Positionseinstellvorrich processing according to this invention in different Relativpo sitions,

Fig an enlarged view taken. 5 along the generally by the lines 5-5 in Fig. 3 plane shown,

Fig. 6 is an enlarged view taken generally along the plane shown by lines 6-6 in Fig. 4, and

Fig. 7 is an exploded perspective view of the Positionstellstellvor direction according to this invention.

As shown in FIGS . 1-2, a tiltable and telescopic automotive steering column 10 includes a pillar shell 12 consisting of a tubular lower pillar shell 14 and a tubular upper pillar shell 16 which telescopically overlaps the lower pillar shell. A steering shaft 18 is supported on the pillar shell 12 for rotation about a longitudinal centerline 20 of the latter. A steering wheel 22 is rigidly arranged at an obe ren end of the steering shaft 18 for rotation as a unit with this.

The column jacket 12 is vertically pivotable about a geometric center 24 on a body of the motor vehicle, not shown, in order to adjust the vertical position of the steering wheel 22 between limits which are represented by upper and lower positions 20 ', 20 ''of the center line 20 . The position of the upper column jacket 16 on the lower column jacket 14 is variable in the direction of the longitudinal center line 20 in order to adjust the horizontal position of the steering wheel 22 between inner and outer limit positions 22 ', 22 ''. A position adjuster 26 according to this invention between the upper pillar shell 16 and a schematically illustrated body structure 28 of the motor vehicle holds the horizontal and vertical positions of the upper pillar shell 16 and therefore the horizontal and vertical positions of the steering wheel 22 .

As best seen in Figs. 1, 2 and 7, the Positionein adjusting device 26 includes an outer bracket 30 in the shape of an inverted "U" and a wing-shaped bracket 32 which is welded to the outer bracket. The outer carrier 30 has, on opposite sides of the upper column shell 16, a pair of vertical sides 34 A, 34 B. The winged bracket 32 is rigidly attached to the body structure 28 by suspension bolts and capsules, not shown, which separate the winged bracket to allow an energy absorbing compression stroke of the steering column 10 in the event of an impact on the steering wheel 22 .

An inner bracket 36 of the position adjuster 26 in the form of an inverted "U" is disposed within the outer bracket 30 and welded to the upper pillar shell 16 . A pair of vertical sides 38 A, 38 B of the inner carrier is set next to the respective vertical sides 34 A, 34 B of the outer carrier 30 . The vertical side 38 A of the inner carrier is placed between the vertical side 34 A of the outer carrier and a friction plate 40 , which is on the vertical side 34 A by a tab 42 on the vertical side 34 A in a slot 44 in the friction plate, Fig. 7 is attached. In the vertical sides 34 A, 34 B of the outer carrier 30 , respective slots of a pair of substantially vertical slots 46 A, 46 B are provided. In the vertical sides 38 A, 38 B of the inner support 36 , a pair of horizontal slots 48 A, 48 B are provided parallel to the longitudinal center line 20 of the column jacket. An elongated window 50 is provided in the friction plate 40 .

Sawtooth notches on the edges of a pair of integral flanges 52 on the vertical side 34 B of the outer bracket on opposite sides of the vertical slot 46 B define an outer rack 54 of the position adjuster 26 . Sawtooth notches on the edges of a pair of integral flanges 56 on the vertical side 38 B of the inner bracket on opposite sides of the horizontal slot 48 B define an inner rack 58 of the position adjuster 26 .

A cylindrical adjusting shaft 60 of the position adjusting device 26 it extends through the vertical and horizontal slots 46 A-B, 48 A-B, where these intersect, and through the elongated window 50 in the friction plate 40 . During a vertical adjustment of the column jacket 12 , the adjusting shaft moves up and down between the ends of the vertical slots 46 A, 46 B as a unit with the inner support 36 and the upper column jacket 16 . During a horizontal adjustment of the upper column jacket 16 , the horizontal slots 48 A, 48 B in the inner carrier 36 reciprocate over the adjusting shaft 60 , which in the direction of the longitudinal center line 20 of the column jacket through the edges of the vertical slots 46 A, 46 B. is limited.

A pair of plastic spacers 62 on the adjustment shaft 60 center the last one at the intersections of the vertical and horizontal slots 46 A-B, 48 A-B, thereby cooperating to support rotation about a transverse center line 64 of the position adjuster 26 when the adjustment shaft is supported on the inner and outer brackets 36 , 30 . The adjustment shaft 60 includes a pair of flat sides 66 along their full length, a threaded end 68 and a serrated head 70 opposite the threaded end that defines an annular shoulder 72 in a plane perpendicular to the transverse centerline 64 . A Handeinstellhe bel 74 is rigidly brought by a holder 76 on the jagged head 70 for rotation as a unit with the adjusting shaft around the transverse center line 64 between a locked position and an unlocked position, each in FIG. 1 in a solid or dashed lines are illustrated.

As best seen in FIGS. 3, 4 and 7, the operating is comprises adjusting device 26 further includes an outer rack shoe 78 and an inner rack shoe 80 on the adjustment shaft 60, each facing the externa ßeren rack 54 and the inner rack 58 , an outer leaf spring 82 and an inner leaf spring 84 on the adjusting shaft behind the outer rack shoe and the inner rack shoe, respectively, and an outer cam block 86 and an inner cam block 88 on the adjusting shaft behind the outer leaf spring and the inner leaf spring, respectively . Each rack shoe 78 , 80 includes a window 90 around the adjustment shaft, a rack 92 interrupted by the window, a pair of guide tabs 94 on opposite longitudinal ends of the window, a pair of retaining tabs 96 , each interrupted by a slot 98 , and a rotary projection 100 in the center of the rack shoe perpendicular to the rack 92 , which is interrupted by the window 90 . Each cam block 86 , 88 includes a circular bore 102 around the adjustment shaft, a pair of tabs 104 at opposite ends of the cam block, and a counterbore 106 around the bore 102 . Each leaf spring 82 , 84 includes a central opening 108 around the adjustment shaft, a plurality of fingers 110 at the four corners of the spring, and a short hook 112 and a long hook 114 , each extending in the opposite direction from the fingers 110 .

The fingers 110 of the leaf springs 82 , 84 resiliently grip the sides of corresponding cam blocks of the cam blocks 86 , 88 to hold the springs and the cam blocks together, the springs lying flush on the cam blocks. The short and long hooks 112 , 114 on the leaf springs 82 , 84 are hooked over the guide projections 94 to correspond to the rack shoes of the rack shoes 78 , 80 through the fen 90 in the rack shoes. The short hooks 112 rock the corresponding rack shoes of the rack shoes 78 , 80 about the rotating projections 100 on the cam blocks 86 , 88 in tilted positions, FIG. 6, which are generally fixed by an engagement of the rack shoe on an edge of the cam block. The tabs 104 on the cam blocks cooperate with the slots 98 in the holding ridges 96 on the rack shoes to prevent relative rotation between the cam blocks and the rack shoes about the transverse center line 64 .

The outer rack shoe 78 , the outer leaf spring 82 and the outer cam block 86 form an outer jaw of the position adjusting device, which is in a linear movement towards the outer toothed rack 54 to and away from it in the direction of the transverse center line 64 . The inner rack shoe 80 , the inner leaf spring 84 and the inner cam block 88 form an inner jaw of the position adjusting device, which is in a linear movement to the inner rack 58 to and away from this in the direction of the transverse center line 64 ver. The adjustment shaft 60 is rotatable about the transverse center line 64 relative to the inner and outer jaws. The guide protrusions 94 on the outer rack shoe 78 cooperate with the edges of the vertical slot 46 B to prevent rotation of the outer jaw about the transverse center line 64 . Likewise, the guide tabs 94 on the inner rack shoe 80 cooperate with the edges of the horizontal slot 48 B to prevent rotation of the inner jaw about the transverse center line 64 .

Each of the inner and outer jaws has an open position in which the racks 92 on the outer and inner rack shoes 78 , 80 are laterally separated from the outer and inner racks 54 , 58 , respectively. The open position of only the outer jaw is illustrated in FIG. 6. Each of the outer and inner jaws has a closed position in which the racks 92 on the outer and inner rack shoes 78 , 80 mesh with the outer and inner racks 54 , 58 , respectively. The closed position of only the outer jaw is illustrated in FIG. 5. It is important that in the open positions of the inner and outer jaws, the racks 92 on the outer and inner rack shoes 78 , 80 define entry angles θ, Fig. 6, relative to the outer and inner racks 54 , 58 .

A movement converting means 116 of the position adjusting device 26 converts a pivoting movement of the adjusting lever 74 between its locked and unlocked positions into a linear movement of the respective outer or inner clamping jaws between their respective closed or open positions. In addition to the adjusting shaft 60, the movement converting means 116 further includes a short cam cylinder 118 on the adjusting shaft 60 between a nut 120 on the threaded end 68 of the shaft and the outer cam block 86 , a pressure shoe 122 on the adjusting shaft adjacent to the friction plate 40, and a long cam cylinder 124 on the actuating shaft a between the inner cam block 88 and the pressure shoe 122nd Inner bores in the short cam cylinder 118 and the long cam cylinder 124 , which are shaped like the setting shaft 60 , connect the short and long cam cylinders to the setting shaft for rotation therewith about the transverse center line 64 and for a reciprocating linear movement in Direction of the transverse center line.

A bore 126 through the pressure shoe enables a relative rotation between the adjusting shaft and the pressure block. A flat side 128 of the pressure shoe 122 faces the friction plate 40 , and a pair of guide tabs on the flat side 128 protrude through the elongated window 50 in the friction plate into the horizontal slot 48 A in the vertical side 38 A of the inner carrier 36 . The guide tabs cooperate with the edges of the horizontal slot in preventing the pressure shoe from rotating about the transverse center line 64 .

As best seen in FIG. 7, an annular cam 130 at one end of the short cam cylinder 118 faces a plurality of cam followers 132 in a counterbore around the bore 102 in the outer cam block 86 . An annular cam 134 at one end of the long cam cylinder 124 faces a plurality of cam followers, not shown, in a depression in the inner cam block 88 like the cam followers 132 on the outer cam block. An annular cam 136 at the other end of the long cam cylinder 124 is facing a plurality of cam followers 138 in a depression in the pressure shoe 122 around the bore 126 in the last one. A pair of coil springs 140 around the adjustment shaft 60 on opposite sides of one of the spacers 62 lie on the outer and inner leaf springs 82 , 84, respectively, thereby biasing each of the outer and inner jaws toward their open positions. In addition, the springs 140 maintain contact between the annular cams 130 , 134 , 136 and the corresponding cam followers on the cam blocks and on the pressure shoe.

When the adjustment lever 74 is in its unlocked position, the cam followers on the cam blocks 86 , 88 and on the pressure shoe 122 are aligned with the deepest segments of the annular cams 130 , 134 , 136 , and the inner and outer jaws decrease due to that Bias the springs 140 to their open positions, Figs. 4 and 6. In the open positions of the inner and outer jaws, the racks on the outer and inner racks shoes 78 , 80 are respectively removed from the outer and inner racks 54 , 58 , so that the column jacket 12 is freely adjustable vertically and horizontally. As described above, each of the racks 92 on the inner and outer rack shoes defines the entry angle θ relative to the corresponding rack of the inner and outer racks 58 , 54 .

In order to simultaneously hold the horizontally and vertically adjusted positions of the column sleeve 12 , an operator swivels the adjusting lever 74 by hand from its unlocked position into its locked position. Egg ne corresponding rotation of the adjusting shaft 60 and the cam cylinders 118 , 124 thereon by the annular cams 130 , 134 , 136 and the corresponding cam followers in a linear movement of the inner and outer jaws on the outer and inner racks 54 , 58 to transformed. Because of the entry angle θ, the initial engagement between the rack 92 on the outer rack shoe 78 and the outer rack 54 is on an end tooth 142 of the first and a mating tooth 144 of the last. Thereafter, simultaneously with a continued linear movement of the outer jaw into its closed position, the reaction force of the matching tooth 144 on the end tooth 142 bounces or pivots the outer rack shoe 78 around the raised projection 100 on the outer cam block 86 against a restoring force caused by the outer leaf spring 82 is initiated until the outer rack shoe 78 is parallel to the outer rack 54 and the rack 92 on the rack shoe fully intermeshes with the outer rack. The rack 92 on the inner rack shoe 80 and the inner rack 58 cooperate simultaneously and identically to achieve full engagement in the locked position of the adjustment lever 74 .

Rotation of the cam cylinders 118 , 124 relative to the cam blocks 86 , 88 and the pressure shoe 122 also clamps the side 128 of the pressure shoe and the flange 72 to the head 70 of the adjusting shaft 60 on opposite sides of the adjacent stack, which consists of the vertical ones Pages 34 A, 38 A of the outer and inner supports 30 , 36 and the friction plate 40 , together. The friction that is introduced between the vertical sides 34 A, 38 A and between the vertical side 38 A of the inner carrier and the friction plate 40 complements the holding function of the aforementioned inner and outer jaws with respect to the horizontally and vertically adjusted positions of the pillar jacket 12 .

As shown in Figs. 3-6, the entry angle θ between the rack 92 on the outer rack shoe 78 and the outer rack 54 and between the rack 92 on the inner rack shoe 80 and the inner rack 58 is smooth engagement of the racks regardless the relative positions of the racks. For example, if the relative positions of the racks 54 , 92 cause tip-to-tip engagement between the end tooth 142 of the rack 92 on the outer rack shoe and the mating tooth 144 of the outer rack 54 while the adjusting lever 74 is in its unlocked position in its is locked position, the aforementioned pivoting movement of the rack shoe 78 about the transverse rotation projection 100 , which is initiated by the reaction force of the fitting tooth on the end tooth, a tip 146 of the end tooth 142 relative to the tip of the matching tooth in the direction of the racks 54 , 92 . Such a displacement moves the tip 146 of the end tooth 142 to a flank of the matching tooth, whereby the racks 54 , 92 are aligned relative to each other for a smooth engagement, while the rack shoe 78 at the same time reaches a parallelity with the outer rack 54 .

A position adjusting device 26 for an adjustable steering column 10 comprises, in summary, a first toothed rack 54 , a cam block 86 which can be moved in and out of the first toothed rack in a linear movement, a toothed rack shoe 78 on which a second toothed rack 92 is provided and which attached to the cam block for linear movement therewith and for pivotal movement therewith, and a spring 82 which biases the rack shoe to a tilted position on the cam block. An end tooth 142 of the second rack 92 is engaged with a mating tooth 144 of the first rack 54 when the cam block 86 is advanced to the first rack. The force response of the mating tooth to the end tooth pivots the rack shoe 78 relative to the cam block 86 to a position parallel to the first rack 54 in which the first and second racks mesh. When a tip 146 of the end tooth 142 meets a tip of the mating tooth 144 , pivotal movement of the rack shoe 78 displaces the tip of the end tooth to a flank of the mating tooth, thereby aligning the tips of the teeth on the first and second racks and to prevent a corresponding disturbance of a smooth engagement between the first and the second racks.

Claims (3)

1. Position adjustment device ( 26 ) for a motor vehicle steering column ( 10 ), which has a column casing ( 12 ) which is adjustable relative to a body of the motor vehicle over a range of adjustment positions, comprising:
a pair of carriers ( 30 , 36 ), each with a respective part of the body of the motor vehicle or the steering column jacket a related party and a pair of side-by-side ( 34 A, 38 A, 34 B, 38 B) having the same time an adjustment of the column cover over the range of adjustment positions relative to one another, which are displaceable,
an adjusting shaft ( 60 ) which protrudes through an opening ( 46 A, 46 B, 48 A, 48 B) in each of the side-by-side sides ( 34 A, 38 A, 34 B, 38 B) of the carriers ( 30 , 36 ), so that one of the side by side ( 34 B) moves simultaneously with an adjustment of the column cover over the range of adjustment positions relative to an adjustment shaft in a plane perpendicular to the adjustment shaft,
a first rack ( 54 ) on one of the juxtaposed sides ( 34 B), and
a jaw on the adjusting shaft ( 60 ) for a linear movement towards and away from the first rack ( 54 ) between a locked position in which a second rack ( 92 ) on the jaw with the first rack on the one of the ne side by side ( 34 B) combs, and is carried in an unlocked position in which the second rack ( 92 ) is removed from the first rack,
characterized by
that the jaw includes:
a cam block ( 86 ) which is carried on the setting shaft ( 60 ) for a linear movement towards and away from the first rack ( 54 ),
rotation protrusion means ( 100 ) on the cam block ( 86 ),
a rack shoe ( 78 ) which on the adjusting shaft ( 60 ) for linear movement towards and away from the first rack ( 54 ) as a unit with the cam block ( 86 ) and for a pivoting movement relative to the cam block around the rotational jump ( 100 ) carried around
wherein the second rack ( 92 ) on the rack shoe ( 78 ) is formed GE, and
a spring means ( 82 ) between the rack shoe ( 78 ) and the cam block ( 86 ), which causes the rack shoe in a ge tilted position relative to the first rack ( 54 ) in the unlocked position of the jaw, so that simultaneously with egg ner linear Movement of the jaw from the unlocked position to the locked position, an end tooth ( 142 ) of the second rack ( 92 ) first engages with a matching tooth ( 144 ) on the first rack ( 54 ), and a corresponding reaction force of the matching one Zahns on the end tooth pivots the rack shoe in a position parallel to the first rack, in which the first and the second racks ( 54 , 92 ) mesh without a tip-to-tip interference. 2. Position adjusting device ( 26 ) according to claim 1, further comprising:
an adjusting lever ( 74 ) rotatable as a unit with the adjusting shaft ( 60 ), and
movement converting means for converting rotation of the adjusting shaft ( 60 ) into linear movement of the jaw from the locked position to the unlocked position, and that
an annular cam ( 130 ) which is rotatable as a unit with the adjusting shaft ( 60 ), and
a cam follower ( 132 ) on the cam block ( 86 ) which is engageable with the annular cam. 3. Position adjusting device ( 26 ) according to claim 2, wherein the spring means ( 82 ) between the rack shoe ( 78 ) and the cam block ( 86 ) comprises:
a flat leaf spring ( 82 ),
a plurality of fingers ( 110 ) on the flat leaf spring ( 82 ) which resiliently grip the cam block ( 86 ) to couple the flat leaf spring and the cam block together, and
a pair of hooks ( 112 , 114 ) on the flat leaf spring ( 82 ) which grip the rack shoe ( 78 ) and rock the rack shoe about the rotation protrusion ( 100 ) on the cam block to the tilted position of the rack shoe.